[dpierce9]

This doesn’t seem right to me. Is this 200k per dispenser? The dispenser is really just a fancy switch and a plug in a kiosk. If you are talking about the central transformer/switching systems, then yes that makes sense. But you can add a lot of dispensers to that.

A pump is only 25k to install if you don’t include the infrastructure to support the pump (tank, canopy, fire suppression, filters, etc).all that costs more than 200k.

Let’s say 25k is the marginal cost for an extra pump. What is the marginal cost for an extra dispenser?

[Kirby64]

DCFCs are much more than a “fancy switch”. It’s a circuit capable of converting 3-phase high voltage AC into variable high voltage DC at 150-350kW. The power electronics are very, very expensive. As far as I’m aware, the large transformer you see usually hidden somewhere nearby is not the primary cost (although it is expensive, especially for very high wattage ones).

And yes, it’s 200k per dispenser including the infrastructure. It doesn’t scale as well as you think it does. I think Tesla has been quoted as around 50k per dispenser including infra though, so some of it is just poor efficiency in costs by other mfgs.

[dpierce9]

The fast charger is the expensive part, the dispenser is not nearly so. Just like a gas station, dispensers to chargers are many-one. I was being a bit glib when I said the dispenser is a fancy switch (esp if the lines are cooled) but only just a bit.

I see a report that has Tesla’s cost as 43k per installed dispenser. That is a fully load cost, not the marginal cost of dispenser but it is good enough.

Looking at listings for gas stations for sale (with a convenience store but no auto repair), I see about 150-300k per dispenser. That isn’t exactly apples to apples but suffice to say it isn’t exactly cheap and much closer to representing the cost than the cost of a pump (which is I assume cheaper than a dispenser).

[Kirby64]

At least the Tesla implementation of their latest stuff, dispenser to faster charger ratio is 1:1. Their older design would gang 2 dispensers to a single 150kW combined charge rate, but new ones are 250kW per dispenser for each port simultaneously.

[kccqzy]

The expensive power electronics you speak of are not part of the dispenser. The dispenser is really just a very fancy switch. It performs some payment authorization and then switches on those expensive power electronics.

If you look at a modern Electrify America unit, the dispenser is an extremely slim panel with a screen. It clearly isn't big enough to contain these power electronics.

Now transformer isn't a great name because it implies an AC-to-AC device which this is not. So I can see where the confusion comes from.

[Kirby64]

I’m not confused here, to be clear. There is a giant transformer that converts from mid voltage AC to low voltage AC at most installations. Because they draw so much power they need their own dedicated transformers. There’s sometimes (depending on the installation) a separate cabinet to convert the AC to DC and then transfers it to dispensers, though, as you say. The more modern high power ones tend to use separate cabinets, I’d agree. Older ones could take 3-phase AC directly since they’re much lower power overall.

[vel0city]

Those older ones were just normal step-down transformers. In Europe that would often be three-phase, in the US it would normally be two-phase (J-1772 is only two-phase compatible). In that world, the "charger" (EVSE) was just a smart relay which would tell the car how much power the circuit would handle, but the actual charger was a thing in the car. That's commonly called Level 2 charging.

What is commonly talked about here are DC fast chargers, where the actual "charger" is an AC to DC cabinet on-site. Those chargers could be connected to one or many dispensers. The dispensers are the things with the cables that plug into the car, handle payment negotiation, and relay battery state to the charger in the cabinet. You could have multiple dispensers to chargers in this setup.

The technical English parlance here would be EVSE for the Level 2 chargers (the smart relay things), and dispensers for the pedestals with the cables for DC fast chargers (DCFCs).

[Kirby64]

Again, not confused here. I’m talking about older stuff like the 50kW CCS/chademo systems. There’s no “older” with standard level 2 charging. Level 2 charging coexists with level 3 and will continue to coexist.

[cyberax]

That's because the power electrics are in a big white cabinet on the side.

DCFC electrics are absolutely insane.

[bangaladore]

Exactly. I would be surprised if frankly Tesla's cost to open a decent supercharging station (6-10 stalls or something) is greater than the cost to open a 4 stall gas station.